Various devices, such as, by way of a non-limiting example, smart cards, SIMs, and so on, comprise electronic circuitry and memory, and do not comprise a power source. Such devices may comprise hardware or software implementations of programs which depend on time data.
One such device, by way of a non-limiting example, is a SIM card providing DRM services to a cell phone handset. Such a device generally does not advance time when the device is cut off from power, such as when the SIM card is withdrawn from the handset. When the device regains electric power, the device can update time by communicating with a time source, such as a timer kept in the handset. Additionally, both the SIM card and the handset may be cut off from power, when a cell phone handset battery is withdrawn from the cell phone handset. Upon reinserting the battery into the cell phone handset, the cell phone handset typically asks a user whether to update time, the time update being typically performed by communicating with a time source provided by the cell phone service company.